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Questions tagged [linked-data]

Linked Data refers to a set of best practices for publishing data on the Web under the Semantic Web standards (RDF, SPARQL, etc.). Please consider asking your question on https://opendata.stackexchange.com, if your question is not closely related to programming or is related to a particular Linked Data dataset.

T. Berners-Lee outlines four principles of linked data in his "Linked Data" note:

  1. Use URIs as names for things
  2. Use HTTP URIs so that people can look up those names
  3. When someone looks up a URI, provide useful information, using the standards (RDF*, SPARQL)
  4. Include links to other URIs, so that they can discover more things
371 questions
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Columns and rows in SPARQL query result

I have a problem here, it looks easy but because I am not really familiar with Sparal queries I could not find a solution for it. PREFIX onto: PREFIX resu: PREFIX yago:…
MR BIG
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How to set up the ID of a json element in rdflib

Context I am loading a rdf file in rdflib, and am trying to export it in json-ld. The original rdf looks like: A substation The exported…
Guillaume
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With multiple SERVICE clauses and large numbers of relationships in the path, how to execute SPARQL federated query statement?

Regarding the following SPARQL federated query statements: There are over 10000 ?s2 related to ?s1 There are over 10000 ?s3 related to the previously found ?s2 There are over 10000 ?s4 related to the previously found ?s3 There are over 100 ?s5…
chenkun
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What is the logic of the SPARQL CONSTRUCT LIMIT?

What is the logic of LIMIT when using CONSTRUCT queries in SPARQL? When I use CONSTRUCT to query DBpedia, I find that the results sometimes don't match the LIMIT Example SPARQL: CONSTRUCT { ?s a ?sType . ?s ?p ?o . ?o a ?oType . } WHERE { …
chenkun
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Specify subframe for elements of id-value property map in a JSON-LD frame

I am trying to write a JSON-LD frame that serializes some RDF documents in a consistent way. Currently, the RDF is being parsed out from JSON-LD that is correctly structured and I would like the frame to return it in exactly the same way as it came…
qqq
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Is the Knowledge Graph and the Linked Open Data the same thing?

I started to dive into the topic "Knowledge Graph" and I get the feeling that this is the same as the "Linked Open Data". I have some questions 1) If so, why did they need to invent a new concept. 2) If not, what is the difference and what does…
iroli
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Rdflib and activitystreams

so I'm investigating rdflib to use with ActivityStreams. My current main goal is to input an Object and get the same one back! My current try looks like this import rdflib G =…
Helge
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How to get RDF data returned by remote HTTP IRI through linux curl (e.g. DBpedia, GENEPIO ...)?

I know that the following remote HTTP IRI can be parsed directly with 'curl http://xxx' because they return RDF data…
chenkun
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retrieving the countries details from geonames using a sparql query

I am trying to get specific countries informations from geonames using "Linked Data HTW Chur sparql endpoint" (url: http://linkeddata.fh-htwchur.ch/lodestar/sparql ): PREFIX gn: PREFIX wgs84_pos:…
amine4392
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skos:related vs skos:relatedMatch

Can someone explain to me the difference between skos:related and skos:relatedMatch predicates? My current understanding is that skos:related applies to concepts that are related "within" a scheme, whereas skos:relatedMatch is to concepts across…
AnonymousMe
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Why does Activity Pub make servers wrap "Note" objects into "Create" activities?

What I've gathered is that new posts are published by POSTing a JSON-LD Activity Streams object of type Note to an actor's outbox. {"@context": "https://www.w3.org/ns/activitystreams", "type": "Note", "to": ["https://chatty.example/ben/"], …
Gian
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SPARQL Federated Query takes too long to respond

I have a SPARQL federated query where I join data from wikidata and dbpedia. When I run the first two queries it takes reasonable time. However, when I add the 3rd service it takes too much time. In the 3rd query I fetch the entities obtained from…
cuneyttyler
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Alias a JSON-LD keyword and simultaneously provide a @context for it

I have the following JSON document (based on GitHub API output): { "@id": "https://github.com/octadocs/octadocs", "license": { "key": "mit", "name": "MIT License", "spdx_id": "MIT", "url": "https://api.github.com/licenses/mit", …
Anatoly Scherbakov
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How to import the OWL classes as a Node in Neo4j?

I am working on Neo4j, and I imported my ontology, but I didn't understand how Neo4j import the class owl:NamedIndividual or the other class other than owl:Class, because it gives me just one node label which is Resource, there aren't any way to…
Curious
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How best to describe material of parts of a schema.org/Product in JSON-LD?

The schema.org/Product type has a material property for “[the] material that something is made from.” I'd like to describe the materials that each part of a product is made from. For example, suppose I have a carbon fiber bike with wood handles and…
King Chung Huang
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